Three-dimensional weaving technology is called one of the most advanced manufacturing technologies for composites worldwide at present. The three-dimensional weaving is a technology to manufacture a three-dimensional seamless whole structure through interweaving long fibers and short fibers, and the process feature of the three-dimensional weaving is that it can manufacture a solid with regular or irregular shape and enable the formation of multifunctional structure, that is, a multi-layer integral structure can be weaved.
In the early 80s, Dr. R. Florentine in Quadrax Advanced Materials Company proposed a four-step processing technology. In 1988 Popper and McConnell in Dupont developed a two-step processing technology, and completed the theoretical system of three-dimensional weaving process. Three-dimensional woven fibers interweave and intercross with each other in a three-dimensional space, and they interweave together not only in a plane but also in the thickness direction, so that a non-layered integral structure is formed, which improves the whole performance of the woven piece. The development of this technology promotes the application of multidirectional reinforced composites in the aviation industry, and attracts enormous attention from research institutions and companies in various countries. However, three-dimensional weaving technology is used mostly in processing preforms with little sectional dimension change, and for preforms with complex shapes, it is necessary to change the arrangement or quantity of fibers during the weaving, which makes the processing procedure complex and the automation control difficult.
Chinese patent No. ZL200820078572.1 discloses a three-dimensional and full five-direction weaving technology and its weaving equipment thereof. In clearances formed by the intersected paths of weaving bundles of a three-dimensional five-direction weaving structure, axial bundles are added along axis direction of weaving, so that the axial performance of the woven materials is improved. However, the specific weaving path mentioned in this method is still along the three-dimensional orthogonal directions and the weaving is executed along row tracks and column tracks, therefore the shapes and the dimensions of the woven preforms are limited, and simultaneously, the woven preforms are lack of high bearing capability and overall performance.
Especially in recent years, with the rapid development of the aerospace industry and the national defense industry or the like in China, requirements on the three-dimensional weaving technology for composites are rapidly increasing. The traditional three-dimensional weaving technology for the preforms has difficulties in processing complex and large structure parts, therefore the research trend in various countries is to continuously improve and develop the weaving process, the adaptability of weaving on the basis of guaranteeing the whole performance of preforms, and promote the application of the three-dimensional weaving technology in fabricating structural parts with complex section, large sectional dimension changes and large dimensions.